The Meteor-M-2 (also referred to as Meteor-M2, or as Meteor-M N2) satellite is a Roskosmos/Roshydromet/Planeta (Moscow, Russia) follow-on polar-orbiting meteorological mission to Meteor-M-1 (launch Sept. 17, 2009). The overall objectives of the Meteor-M-2 mission are to provide global observations of the Earth's surface and its atmosphere. The data acquired by the satellite is used for the following purposes:

Table 1: Overview of the sensor complement of the Meteor-M2 and Meteor-M2-1 missions

Roskosmos plans to launch five similar satellites with the same payload as Meteor-M2, i.e. Meteor-M2-1, Meteor-M2-2, Meteor-M2-3, Meteor-M2-4, Meteor-M2-5. The goal is to create a system of identical operational meteorological satellites in the morning and afternoon orbits.

Regarding the future Meteor-M3 oceanographic satellite, this spacecraft is currently under development. Its payload will consist of:

The Meteor-M spacecraft series are developed by RSC (Research and Production Corporation) VNIIEM , Moscow as prime contractor to Roskosmos. Each satellite in the series has a mass of ~2,800 kg including ~1,250 kg for the multi-instrument payload suite of the satellites. The Meteor-M satellites share a series of common instruments, but some instruments are specific to each spacecraft to increase the amount of available data.

The Meteor-M2 spacecraft consists of large cylindrical body structure, two deployable sun-tracking solar arrays, a large deployable synthetic aperture radar antenna and a rectangular payload deck that hosts the majority of the instruments and instrument apertures of the satellite being pointed to Earth for observations.

The spacecraft is three-axis stabilized. Attitude sensing is being provided with a star tracker, referred to as BOKZ-M. The S/C pointing accuracy is 0.1º, the angular drift rate is 0.0005º/s. A navigation subsystem (GPS/GLONASS receiver) provides orbit determination and timing services.

The BOKZ-M star tracker is of Resurs-DK1 (launch June 15, 2006) heritage. The BOKZ family instrument is a monoblock with the digital TV camera based on a CCD array detector, a signal processor based computer and a secondary power supply unit. The instrument is providing a pointing accuracy of 2 / 20 arcsec (x, y / z), the attitude data is updated at a frequency of 0.3 Hz, the instrument has a mass of 4 kg, power consumption of 11.2 W, and a size of 37 cm x 23 cm x 23 cm.

Solar power of 2 kW (BOL) is provided by two deployed panels which are continuously sun pointed for optimum power generation (solar panel area of 23 m2, solar array span of 14 m).

The S/C launch mass is 2778 kg (payload mass of ~1200 kg). The S/C design life is 5 years with a goal of additional service provision.

Launch: The Meteor-M2 spacecraft was launched on July 8, 2014 (15:58:28 UTC) with a Soyuz-2.1b/Fregat launch vehicle of NPO Lavochkin. The launch site was the Baikonur Cosmodrome, Kazakhstan. 2)3)4)5)

The planned mid-December 2013 launch has been delayed again following the latest series of issues with the primary satellite payload. Russia's Meteor-M2 polar-orbiting meteorological satellite has faced delays in the past that have kept the secondary payloads — Norway's AISSat-2, Canada's M3MSat, Britain's TechDemoSat-1 and UKube-1 among them — on the ground.6)

The Soyuz delay follows a two-year grounding of the Russian-Ukrainian Dnepr silo-launched rocket, which small-satellite owners hope may now be returning to the market pending an agreement between Russia's military space forces and the Russian space agency, Roskosmos.

In late April, the Canadian government suspended preparations for sending its M3MSat microsatellite to Russia due to the current situation of unrest in Ukraine, citing Russia's actions in the Ukraine. This is the Canadian government's hardline response on sanctions against Russia.

The M3MSat mission is financed jointly by the DRDC (Defense Research and Development Canada) and CSA (Canadian Space Agency). Officials of CSA and COM DEV, the builder of M3MSat, are now trying to find another country or private company willing to send the surveillance satellite into space.

Canada has imposed economic penalties on a number of Russian companies and individuals and cancelled a planned military exercise with the Russian air force. It also expelled an attaché from the embassy in Ottawa.

COM DEV issued a statement on April 24, 2014 that it would not proceed with the launch of M3MSat. "Recognizing the current events in the Ukraine, we had been engaged in discussions with the Government of Canada with respect to a potential delay of the launch of M3MSat, and plans to mitigate the impact of any delay."

Commenting on the Canadian media reports that the government's hard line on sanctions against Russia has scuttled the launch of M3MSat, Russian Deputy Prime Minister Dmitry Rogozin responded: "Canada will have to pay - both in terms of money and reputation - for a decision to ditch the launch of its satellite by a Russian rocket."

Table 3: The launch of M3MSat was cancelled - a consequence of sanctions on Russia 7)8)

• AISSat-2, a nanosatellite with a mass of ~7 kg of FFI (Norwegian Defense Research Establishment) Norway, built by UTIAS/SFL, Toronto, Canada.

• UKube-1, a nanosatellite (~3.5 kg) of UKSA/Clyde Space Ltd., UK.

Some background: At various points in time, the secondary payloads during the launch of Meteor-M2 also included the Baumanets-2 experimental satellite for the Bauman State Technical University in Moscow, the M3MSat for the Canadian Space Agency and Venta-1 (Ventspils University, Latvia). Baumanets-2 and Venta-1 were dropped from the mission at the early planning stage.
However, the M3MSat ocean-observing satellite, built by COMDEV, was withdrawn from the mission in April 2014 by the Canadian government, as a result of the Russian conflict with Ukraine. In order not to change dynamic parameters of the Fregat upper stage and avoid resulting changes and re-checks of the flight program, mission planners added a mass mockup for the M3MSat, which would be released in orbit, as it had been originally planned for the actual satellite.

Orbit of the secondary payloads: Sun-synchronous near-circular orbit, altitude of ~ 635 km, inclination = 98.8º. The MKS-PN2 (Relek) was released first of the secondary payloads into an elliptical orbit of 632 km x 824 km.

Mission status:

• November 2015: The Meteor-M-N2 spacecraft and its payload (some limitations on Severjanin) are operating nominally. 10)

- MSU-MR instrument is fully functional

- MTVZA-GY instrument is fully functional (absolute calibration work is still ongoing)

• On January 15, 2015, Roskosmos announced that the flight testing of the Meteor-M-N 2 satellite had entered a final phase. The press-release stressed that the prolonged testing was the result of a long list of checks and the complexity of procedures providing the correct operation of onboard systems and high quality of remote-sensing data. The statement went on to say that all calibration and testing efforts provided enough data to conclude that the spacecraft had been ready for operations. By that time, Russian meteorological agency, Roshydromet, joined Roskosmos in processing the satellite's data, the space agency said (Ref. 3).

- Almost half a year after the launch of the Meteor-M2 satellite in July 2014, the Russian space agency, Roskosmos, published a number of press-releases on the flight testing of its newest meteorological satellite along with numerous photos delivered by its instruments. However as important was what was not said or shown — in particular any mentioning of the onboard radar. The 150 kg Severyanin (Northerner) X-band Synthetic Aperture Radar onboard Meteor-M2 satellites was designed to provide all-weather, day-and-night imagery of the Earth surface with a resolution as high as 400 m.

MSU-MR was designed and developed by FSUE/RISDE (Federal State Unitary Enterprise) / Russian Scientific Institute of Space Device Engineering), Moscow. Objective: Global and regional cloud cover mapping, SST (Sea Surface Temperature), and LST (Land Surface Temperature). The optomechanical MSU-MR instrument provides imagery in six bands in the VIS and IR spectral regions (similar in performance and function to the AVHRR/3 instrument on the POES missions of NOAA) with a spatial resolution of 1 km.

KMSS was designed and developed at IKI (Space Research Institute), Moscow. The objective is Earth surface monitoring. The instrument comprises three pushbroom cameras in the VNIR range; two cameras (MSU-100) have a focal length of 100 mm; the third one (MSU-50), has a focal length of 50 mm. The two MSU-100 cameras are tilted ±14º in cross-track to each side of nadir; together they cover a swath width of 960 km, which is close to the swath of MSU-50. 12)

Each camera has a focal plane with 3 CCD lines (each covered with a corresponding filter) behind a common lens. The three-line camera system (with 3 CCD-lines in a focal plane and 1 lens, the corresponding detector elements of different bands look necessarily in different along-track directions) provides the following along-track observation directions: ±17º and 0º (nadir) for MSU-50, and ±8.7º and 0º for MSU-100. The KMSS instrument represents simply the mounting fixture of three separate cameras, and the KMSS image will be an image of 3 separate cameras put together in ground processing.

Figure 8: Illustration of the KMSS cameras (MSU-50 at center and the 2 MSU-100 on each side), image credit: IKI, Roshydromet/Planeta

MTVZA-GY (Microwave Imaging/Sounding Microwave Radiometer)

MTVZA-GY was designed and developed at the Space Observations Center, Moscow, under contract to Roskosmos. The instrument is of MTVZA heritage flown on the Meteor-3M-1 mission (launch Dec. 10, 2001). MTVZA-GY is a passive 29-channel microwave radiometer - similar to the SSMIS (Special Sensor Microwave Imager Sounder) of the DMSP-F16 mission, as well as to NOAA's AMSU-A (Advanced Microwave Sounding Unit-A) and -B radiometers. Note: MTVZA-GY was named in memory of Gennady Ya Gus'kov (1919-2002, Moscow) - the Russian designer of various spaceborne instruments.

The objective of the MTVZA-GY instrument is to monitor ocean and land surfaces as well as global atmospheric parameters such as temperature and water vapor profiles and to obtain sea surface wind profiles. MTVZA-GY is a conical scanning instrument with a common field of view for imaging and sounding channels (simultaneous multispectral and polarization measurements), due to the single antenna design.

The operating frequencies are located in the transparent atmospheric windows at 10.6, 18.7, 23.8, 31.5, 36.7, 42, 48, and 91.65 GHz, as well as in the oxygen absorption lines at 52-57 GHz and water vapor at 183.31 GHz. 13)14)

The instrument consists of a large rotating main reflector and an Instrument Support Structure facilitating the RF electronics and sensors as well as the spin mechanism and support systems. MTVZA-GY has a mass of 90 kg, requires 80 W of power and has a data rate of 35 kbit/s. The operating frequencies of the instrument cover the transparent atmospheric range, the oxygen absorption lines and the water vapor absorption range.

Observation geometry: MTVZA-GY is a conical-scanning radiometer rotating continuously about an axis parallel to the local spacecraft vertical with a period of 2.5 s (24 rpm). The view direction of the instrument is backwards (anti-velocity direction) with a viewing angle of 53.3º and an incidence angle of 65º (with respect the the surface). The scan direction is from the left to the right when looking in the aft direction of the spacecraft, with the active scene measurements in the range from -90º to +15º about the aft direction, resulting in a swath width of 1500 km.

All instrument channels are switched to four feed-horn antennas. MTVZA-GY employs a total-power radiometer design providing a better sensitivity (factor 2) over a conventional Dicke-switched system. The channels in the 10-48 GHz domain are direct amplification radiometers, while the channels in the 52-57, 91 and 183 GHz range are realized as as superheterodyne receivers using balanced mixers. The performance parameters are given in Tables 7 and 8. The following comment applies to Table 7:

• Channels 1-7 and 18 operate on both vertical and horizontal polarization

• Channels 13-17 operate on horizontal polarization only. - Hence, the total number of MTVZA-GY channels amounts to 29.

The antenna system of MTVZA-GY consists of an offset parabolic reflector of dimension 65 cm, illuminated by the four broadband feed-horn antennas. The antenna and radiometers are mounted on a drum for the purpose to provide an invariant viewing and polarization geometry for the reflector scan. The drum contains the various system components like digital data subsystem, power and the signal transfer assembly, which rotates continuously about an axis parallel to the local spacecraft vertical. The power, commands, all data, timing and telemetry signals pass through slip ring connectors to the rotating assembly.

Instrument calibration: Hot and cold reference absorbers are used for calibration. They are mounted on the non-rotating part of the instrument and are positioned such that they pass between the feed-horns and the parabolic reflector, occulting the feed-horns once on each scan. The temperature difference between the hot and cold target is expected to be 50-60 K.

The MSGI-MKA instrument can detect electrons in the energy range of 0.1 to 15 keV, protons at 0.1 to 15 keV in a high- and low-sensitivity channel. Integral electron fluxes can be measured up to 40 keV. The instrument features four channels for the measurement of the following parameters:

The KGI-4C instrument has a mass of 12 kg and a power consumption of 6.8 W (max).

IRFS-2 (Infrared Fourier Spectrometer-2)

The instrument is an advanced infrared sounder with the objective to provide atmospheric temperature and humidity profiles. Note: The Russian abbreviation for the instrument is simply "IKFS".

The IRFS-2 instrument was designed and developed by the Keldysh Research Center. The instrument consists of an optical unit, a data processing and power supply unit and a radiative cooler that keeps the focal plane at an appropriate temperature to reduce the dark current of the detectors. The optical system is comprised of an interferometric module with a double pendulum interferometer and a radiometer, a pointing module and a calibration module. 15)

IRFS-2 covers a spectral range of 5 to 15 µm at a spectral resolution of 0.4 cm-1. The instrument covers a ground swath of 1,000 to 2,500 km with a spatial resolution of about 30 km. The radiometer operates at a radiometric accuracy of 0.5 K. The instrument covers the carbon dioxide absorption band to obtain temperature profiles, two atmospheric windows for cloud properties and surface parameters, the ozone absorption band for ozone sounding and the absorption bands of water, nitrous oxide and methane for moisture profiles and column amount measurement of these substances.

The small size radar Severyanin-M (translation from Russian - "Northerner") is a part of the on-board hardware of the spacecraft Meteor-M series designed and developed by the Research Institute of Precise Instruments, Moscow, Russia. Serveryanin-M is an X-band side-looking radar instrument providing vertical polarization. The main objective is sea ice monitoring in the polar regions, but the radar imagery can also be used for land surface observation, for vegetation monitoring, and a number of other applications. The system consists of two main components: the antenna subsystem and the electric unit. The radar antenna consists of seven segments, six of which are deployed after launch with the central segment attached to the zenith-pointing deck of the satellite. The instrument has a mass of 150 kg and requires 1 kW of power when in operation, the source data rate is 10 kbit/s. 16)

The OBRC instrument operates at a center frequency of 9.623 GHz and an incidence angle range of 25 -48º. A 450 to 600 km ground swath is covered by the radar, depending on the observation mode as it can operate in low and medium resolution mode. In low resolution mode, the radar reaches a ground resolution of 700-1,000 m while the medium resolution mode leads to images with a spatial resolution of 400-500 m.

Parameter

Value

Center frequency (X-band, 3.1 cm wavelength)

9.623 GHz

Incidence angle access range

25-48º

Swath width

450-600 km

Spatial resolution in medium resolution mode

400-500 m

Spatial resolution in low resolution mode

700-1000 m

Source data rate

10 kbit/s

Table 11: Specification of the OBRC instrument

The radar uses an uncontrolled antenna array, klystron transmitter, digital receiver and special digital device for forming the sounding signals, the echoed signals prefiltering and matching to the radiolink. It has embedded facilities for inner amplitude calibration. In addition there is possibility to change parameters of the sounding signal and some other radar parameters through the command radio-link from the Earth.

The spacecraft specifics dictated restrictions on the following radar characteristics:

- radar power consumption: not more than 1 kW

- radar mass: not more than 150 kg (including the antenna mass – not more 40 kg)

- data transfer rate of the radio-link used: not more than 10 kbit/s.

DCS (Data Collection System):

The objective is to collect in-situ data from DCPs (Data Collection Platforms) in the ground segment with location capability.

The information compiled and edited in this article was provided by Herbert J. Kramer from his documentation of: "Observation of the Earth and Its Environment: Survey of Missions and Sensors" (Springer Verlag) as well as many other sources after the publication of the 4th edition in 2002. - Comments and corrections to this article are always welcome for further updates (herb.kramer@gmx.net).